Locomotive-boiler superheater.



W. STEPHAN.

LOGOMOTIVE BOILER SUPBRHBATER.

APPLICATION FILED JANZZ. 1908.

Patented Nov. 29, 1910.

[NYE/{T09 A .4 Tram/Er.

ATNT FTC.

WILLIAM STEPHAN, OF FORT WAYNE, INDIANA.

LOCOMOTIVE-IBOILER SUPERHEATER.

Specification of Letters Patent.

Application filed January 2, 1908.

Patented Nov. 29, 1910.

Serial No. 408,964.

T 0 all whom 'it may concern:

Be it known that I, WILLIAM STEPHAN, a citizen ofthe United States of America, residing in Fort Wayne, in the county of Allen and State of Indiana, have invented a certain new and useful Improvement in L0- comotive-Boiler Superheaters, of which the following is a true and exact description, reference being had to the accompanying drawings, which form a part thereof.

The present invention relates to locomotive boilers, and has for one of its objects the provision in such a boiler of a novel means for superheating the steam generated.

Further objects of the invention are to arrange and dispose the superheating means so that the invention may be employed without requiring any radical changes from the designs of boilers now in use, and without materially, if at all, increasing the dimensions of the boiler to obtain the advantages and increased capacity due to the superheating, and so that the use of the superheating means in a boiler will strengthen and im' prove the construction of the boiler as a whole and will not interfere with the removal or repair of the regular boiler tubes.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this specification.

For a better understanding of the invention and the advantages possessed by it reference may be had to the accompanying drawings and descriptive matter in which I have illustrated and described one form in which it may be embodied.

Of the drawings, Figure 1 is a sectional elevation of a portion of a locomotive boiler taken on the line 11 of Fig. 3. Fig. 2 is a plan view of the superheater pipes, and Fig. 3 is a sectional elevation taken on the line 33 of Fig. 1.

In the drawings, A represents the firebox, B the boiler tube or shell proper, and C the smokebox of a locomotive boiler which in general construction may be like any of the common forms of locomotive boiler. The usual boiler tubes B extend between the firebox and the smokebox within the shell B, being connected into the end walls A and C of the firebox and smokebox respectively. The smoke escapes from the smoke box throu h the usual opening C above which is ocated the smoke stack (not shown). On the upper side of the boiler shell B is provided the usual steam dome B The superheating structure comprises one or more tubular members leading from the firebox to the smokebox. In the form shown there are three of these tubular members D. Each of the tubular members D is connected at its rear end to an elbow E, which extends between the crown sheet A of the boiler and the outer wall A of the firebox and has its lower end opening into the firebox. Each of the tubes D may be secured to this elbow in any suitable manner, as by means of the set of bolts E. The three elbows E may form stays between the crown sheet and the top portion of the outer wall of the double walled firebox. For this purpose, as shown each elbow is formed with a seat above and parallel to the lower end of the vertical leg of the elbow and against this seat a flanged cap-like member E closing an aperture formed in the boiler shell is secured by means of bolts E the arrangement being such that the bolts E may be readily disconnected and connected from the outside of the boiler. The forward ends of the tubes D pass through the smokebox wall C. Tight joints are formed between the tubes D and the smokebox wall C by means of packing rings or collars F surrounding the tubes D and held in place by means of collars F surrounding the tubes D at the inner side of the wall C and flanges on the tubes D outside of the wall G and bolts F which con nect the collars F and the flanges on the tubes. Cup shaped diaphragms D and D are placed in the front and rear end of each of the tubes D. These diaphragms are connected by small tubes D which are located within corresponding tube D and serve to provide channels through which the prod ucts of combustion pass from the elbows E to the smokebox 0. Screens or nettings D are secured to the front end of each of the tubes D to prevent the escape of large solid fuel particles. The spaces within the tubes D between the diaphragms D and D and surrounding the small tubes D form the steam spaces for the steam to be superheated. In the form shown, the steam spaces of the two outer tubes D are connected near their forward ends by an arched tubular connection D and the steam spaces of the right hand andcenter tubes D are connected near their rear ends by a lateral pipe D Apipe D leads from the upper end of the steam dome to the steam space of left hand tube D adjacent the rear end of the latter. Steam drawn from the boiler first passes from the dome B into the tube D through the port D at its upper end, thence along the left hand tube D to the connect-ion D from whence it passes into the righthand tube, and after traveling along the latter passes into the center tube D through the lateral D The branch pipes D leading from the front end of the center tube D convey the steam to the cylinders of the engine.

It will be observed that the steam while passing through each of'the tubes D is sul jected to a very substantial superheating action on account of the hot gases passing through the small'tubes D In consequence, by properly prop'ortioning the size and num ber of the tubes D' and D to the capacity of the boiler any reasonable amount of superheating desired can be obtained.

The entire superheating mechanism is located above the firetubes B proper of the boiler, and in aspace which ordinarily is not occupied by such fire tubes. Indeed the central tube D' occupies the space usually occupied by the so-called dry tube which heretofore has been employed for conveying steam from the dome to the branch pipes D 'run'ning to theengine cylinders. The elbow connections E take the place in part of the stays between the inner and outer walls of the firebox, and the arrangement of these elbow connections is such as to reduce the liability to injury by overheating of the front end of the crown sheet which is the portion most apt to be injured by overheating. The construction of the superheating means is simple and mechanically reliable. Only a comparatively small number of joints are required in its construction and these are so disposed as not to interfere with ready repairs toand renewals of'other portions of the boiler structure, especially with repairs to and renewals of the fire tubes B proper.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is,

1. In a locomotive boiler, the combination with the boiler shell, steam dome and fire and smoke boxes, of one or more elbows secured between the crown sheet or the firebox and the outer wall of the boiler, each elbow serving as a stay rigidly connecting said sheet and wall together and arranged with one leg vertical and opening into the firebox through the crown sheet and the other leg horizontal and opening toward the smokebox, and a set of tubes leading from said other end of each elbow to the smoke box, a large pipe surrounding each set of tubes, and connections to said pipe whereby it serves as a portion of the steam pipe for conveying steam from the top of the steam dome to the steam outlet ofthe boiler.

2. In a locomotive boiler, the combination with the boiler shell, steam dome, firebox and smokebox, of one or more elbows scoured between the" crown sheet of the firebox and the outer wall of the boiler, each elbow serving as a stay rigidly connecting said sheet and wall together and having one branch open to the firebox through thc'crown sheet and the other pointing. toward the smokebox, of a pipe extending from said other branch ot each elbow to the smokebox, a pair of diaphragms in said pipe adjacent its ends, a set of relatively small tubes lo cated within the pipe and extendingthrough the diaphragms, and lateral connections to the pipe between its ends whereby said pipe serves as a portion of the steam pipe for conveying steam from the top of the steam dome to the steam outlet of the boiler, and whereby the steam passing through said pipe is dried or superheated by the furnace gases passing through said tubes.

8. In a locomotive boiler, the combination with the boiler shell, steam dome, firebox and smokebox, of one or more elbows secured between the crown sheet of the firebox and the outer wall of the boiler, and having one branch open to the firebox through the crown sheet and the other pointingtoward the smokebox, of a pipe extending from saidother branch of each elbow to the smokebox, a pair of d iaphragms in said pipe adjacent its ends, a set of relatively small tubes located within the pipe and extendingthrough the diaphragms, and lateral connections to each pipe betweenits ends whereby'said pipe serves asa portion ot the steam pipe for conveying steam from the top of the steam dome to the steam outlet of the boiler, and the steam passingthrough said pipe is dried or superheated by the furnace gases passing through said tubes, and a screen across the smokebox end of each pipe to prevent large pieces of fuel from being carried into the smokebox.

l. In a locomotive boiler the combination with the boiler shell, steam dome and fire and smoke boxes of one or more elboi s each arranged with one downwardly extending vertical leg secured at its lower end to the crown sheet of the boiler and opening therethrough into the firebox and with the other leg horizontal and opening toward the smokebox, each elbow being formed with a seat at its upper side and parallel to and above the lower end of the vertical leg of the elbow, a cap member engaging the outer wall of the boiler and bolted against said seat whereby said elbow serves as a stay rig idly connecting the crown sheet and the outer wall of the boiler and a set of tubes leading from the end of the horizontal leg. of each elbow to the smokebox a large pipe surrounding each set of tubes and connections to said pipe whereby it serves as a portion of the steam pipe for conveying steam from the top of the steam dome to the steam outlet of the boiler.

5. In a locomotive boiler the combination with the boiler shell, steam dome, firebox, smokebox and the main set of tubes connecting adjacent ends of said boxes of three pipes arranged side by side above said set of tubes and connecting each at its opposite ends to the fire and smoke boxes, diaphragms in said pipes adjacent their ends, a set of tubes located in each pipe and open through the end connection thereof to the fire and smoke boxes whereby a superheating space is formed in each pipe between its diaphragms and surrounding the tubes inclosed by it, a steam outlet connection leading from the superheating space of the central pipe at its smoke box end, a connection between the superheating space of the central pipe and one of the other pipes adjacent their firebox ends, a steam supply pipe leading from the upper end 01" said steam dome to the superheating space of the third pipe and a transverse pipe extending over the central pipe adjacent its smoke box end and connecting the superheating spaces of the other tWo pipes.

WILLIAM STEPHAN. Vitnesses HARRY CLARK, F. W. STEPHAN, Jr. 

